VBISX vs. VBLAX

Last updated Jun 6, 2026

VBISX (Vanguard Short-Term Bond Index Fund) and VBLAX (Vanguard Long-Term Bond Index Fund Admiral Shares) are both mutual funds - VBISX is a Short-Term Bond fund managed by Vanguard, while VBLAX is a Total Bond Market fund managed by Vanguard. Over the past 5 years, VBISX returned 1.42%/yr vs -3.39%/yr for VBLAX. A 0.69 correlation means they provide meaningful diversification when combined. VBISX charges 0.15%/yr vs 0.07%/yr for VBLAX.

Performance

VBISX vs. VBLAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Vanguard Short-Term Bond Index Fund (VBISX) and Vanguard Long-Term Bond Index Fund Admiral Shares (VBLAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both stocks are quite close, with VBISX having a 0.26% return and VBLAX slightly lower at 0.25%.

VBISX

• 1D: 0.10%
• 1M: 0.04%
• YTD: 0.26%
• 6M: 0.69%
• 1Y: 3.84%
• 3Y*: 4.14%
• 5Y*: 1.42%
• 10Y*: 1.80%

VBLAX

• 1D: 0.19%
• 1M: 0.51%
• YTD: 0.25%
• 6M: 0.08%
• 1Y: 6.64%
• 3Y*: 2.05%
• 5Y*: -3.39%
• 10Y*: —

*Multi-year figures are annualized to reflect compound growth (CAGR)

VBISX vs. VBLAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
VBISX Vanguard Short-Term Bond Index Fund	0.26%	5.67%	3.66%	4.54%	-5.61%	-1.35%	4.63%	4.28%
VBLAX Vanguard Long-Term Bond Index Fund Admiral Shares	0.25%	6.57%	-4.14%	7.55%	-27.22%	-3.36%	15.75%	16.45%

Correlation

The correlation between VBISX and VBLAX is 0.71, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.71
Correlation (3Y) Calculated over the trailing 3-year period	0.73
Correlation (5Y) Calculated over the trailing 5-year period	0.72
Correlation (All Time) Calculated using the full available price history since Feb 8, 2019	0.69

The correlation between VBISX and VBLAX has been stable across timeframes, ranging from 0.69 to 0.73 - a consistent structural relationship.

Return for Risk

VBISX vs. VBLAX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

VBISX

VBISX Risk / Return Rank: 36
VBISX Sharpe Ratio Rank: 32
VBISX Sortino Ratio Rank: 41
VBISX Omega Ratio Rank: 37
VBISX Calmar Ratio Rank: 38
VBISX Martin Ratio Rank: 33

VBLAX

VBLAX Risk / Return Rank: 9
VBLAX Sharpe Ratio Rank: 9
VBLAX Sortino Ratio Rank: 9
VBLAX Omega Ratio Rank: 8
VBLAX Calmar Ratio Rank: 10
VBLAX Martin Ratio Rank: 9

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

VBISX vs. VBLAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Vanguard Short-Term Bond Index Fund (VBISX) and Vanguard Long-Term Bond Index Fund Admiral Shares (VBLAX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	VBISX	VBLAX	Difference
Sharpe ratio: Return per unit of total volatility	1.55	0.67	+0.88
Sortino ratio: Return per unit of downside risk	2.59	1.00	+1.60
Omega ratio: Gain probability vs. loss probability	1.31	1.12	+0.20
Calmar ratio: Return relative to maximum drawdown	2.24	0.91	+1.33
Martin ratio: Return relative to average drawdown	7.14	2.31	+4.83
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

VBISX vs. VBLAX - Sharpe Ratio Comparison

The current VBISX Sharpe Ratio is 1.55, which is higher than the VBLAX Sharpe Ratio of 0.67. The chart below compares the historical Sharpe Ratios of VBISX and VBLAX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	VBISX	VBLAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.55	0.67	+0.88
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.48	-0.26	+0.75
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.76	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	1.34	0.05	+1.30

Drawdowns

VBISX vs. VBLAX - Drawdown Comparison

The maximum VBISX drawdown since its inception was -8.79%, smaller than the maximum VBLAX drawdown of -38.62%. Use the drawdown chart below to compare losses from any high point for VBISX and VBLAX.

Drawdown Indicators

	VBISX	VBLAX	Difference
Max Drawdown Largest peak-to-trough decline	-8.79%	-38.62%	+29.83%
Max Drawdown (1Y) Largest decline over 1 year	-1.54%	-5.98%	+4.44%
Max Drawdown (3Y) Largest decline over 3 years	-1.55%	-14.92%	+13.37%
Max Drawdown (5Y) Largest decline over 5 years	-8.72%	-36.32%	+27.60%
Max Drawdown (10Y) Largest decline over 10 years	-8.79%	—	—
Current Drawdown Current decline from peak	-0.66%	-24.66%	+24.00%
Average Drawdown Average peak-to-trough decline	-0.87%	-18.12%	+17.25%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.48%	2.34%	-1.86%

Volatility

VBISX vs. VBLAX - Volatility Comparison

The current volatility for Vanguard Short-Term Bond Index Fund (VBISX) is 0.68%, while Vanguard Long-Term Bond Index Fund Admiral Shares (VBLAX) has a volatility of 2.46%. This indicates that VBISX experiences smaller price fluctuations and is considered to be less risky than VBLAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	VBISX	VBLAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.68%	2.46%	-1.78%
Volatility (6M) Calculated over the trailing 6-month period	1.58%	5.63%	-4.05%
Volatility (1Y) Calculated over the trailing 1-year period	2.24%	8.23%	-5.99%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	2.94%	12.88%	-9.94%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.38%	12.64%	-10.26%

VBISX vs. VBLAX - Expense Ratio Comparison

VBISX has a 0.15% expense ratio, which is higher than VBLAX's 0.07% expense ratio. However, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

VBISX vs. VBLAX - Dividend Comparison

VBISX's dividend yield for the trailing twelve months is around 3.90%, less than VBLAX's 4.75% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
VBISX Vanguard Short-Term Bond Index Fund	3.90%	3.44%	3.29%	2.10%	1.38%	1.16%	1.72%	2.16%	1.92%	1.58%	1.42%	1.34%
VBLAX Vanguard Long-Term Bond Index Fund Admiral Shares	4.75%	4.64%	4.61%	4.08%	4.13%	2.62%	5.39%	3.25%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both VBISX and VBLAX in my portfolio?

VBISX and VBLAX have a correlation of 0.71, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, VBISX or VBLAX?

VBLAX has higher volatility (2.46%) compared to VBISX (0.68%). In terms of maximum drawdown, VBISX dropped -8.79% vs VBLAX's -38.62%.

Which has better risk-adjusted returns?

VBISX currently has the higher Sharpe Ratio (1.55 vs 0.67), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.